Hot brakes

[kimlinh]

After a short drive the brakes on my newly restored Model A are very hot. There is some drag when I turn the wheels over when the car is on jack stands but not much( very little). I use the brakes when I take the short drive but not much. The brakes work very well. My question is - is it normal for the drums to get hot to the touch? My modern car does not get hot taking the same trip.

[jg61hawk]

I would think they are just wearing in...but having said that...will the car roll in neutral with the slightest push, or down a very slight grade? Put the parking brake on, then release it and try the rolling thing again. Step on the brakes and release and see if it rolls. If one in hanging up you'll see that right away.

Normally when drum brakes are newly installed there can be a very short period of time that some rubbing on the drum takes place and of course this creates friction = heat. Be careful it's not extreme or they will over heat, and you'll lose the ability to brake effectively. See how it rolls in neutral..to me that tells the story.

[wmws]

I would try to find a place where you can drive for about a mile or so without using the brakes at all and then cost to a stop. Check the drums right away and they should not be hot. Maybe a little warm but certainly cool enough to be able to leave your finger on the drum without burning. If you have used the brakes they will be quite hot. To hot to leave your finger on the drum.

[mhsprecher]

If you don't want to burn your fingers, use an infra red temp gun to measure the temp.

[old victoria]

just finished a brake job( A redo from another shop ) brakes got hot and kept hanging up .discovered when the new drums were pressed on to the hubs they did not turn the drums (they were out of round) turned them no more problems.

[kimlinh]

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The car rolls down hill easily. I'll try the temperature gun next time out. I've been restoring this car for years. What a feeling of accomplishment to finally get it on the road.

[SeaSlugs]

Originally Posted by wmws

I would try to find a place where you can drive for about a mile or so without using the brakes at all and then cost to a stop. Check the drums right away and they should not be hot. Maybe a little warm but certainly cool enough to be able to leave your finger on the drum without burning. If you have used the brakes they will be quite hot. To hot to leave your finger on the drum.

agreed, also dont forget on the rear the drum is centered by the axle tube, wheel bearing, and hub. When its free to dangle all the weight of the rim/drum/axle is pushing down on the probably unworn top side of the axle tube and centered as can be. When the weight is on the car any amount of wear between the hub, bearing, and axle tube add up and now the drum is off centered. Most if not all the wear on the axle tube is the bottom side. as thats where the vehicle weight is pushing against the bearing.

When you say the drum gets hot - you mean out by the braking area and not near the spindle correct?

Also i dont mean to be a donkeys rearend but define restored brakes, ive heard that term restored meaning relining shoes and new springs and paint to actually fully restoring them.

[kimlinh]

SeaSlugs- Yes, when the drums get hot it is out on the breaking area, not the hub. I don't think it is a bearing problem. The Car has new turned drums,bearings, springs, and relined shoes. I'm wondering if it could be a brake rod problem. The hottest drums are the Lt. front and Rr. rear. Also when I put the brakes together I could not find a break shoe grinder so I sanded the shoes to fit the drums.

Thanks everybody for the responses.

[Big hammer]

Kimlinh, sent you a PM

[100IH]

At this point I would remove the drums and look at the linings for the shiny spots that are the contact spots creating the heat. The high spots could be sanded or filed just a bit to speed up the wearing in process unless it is so out of position so as to indicate a further correction, such as modifying the roller tacks. A judgement call.

[katy]

The hottest drums are the Lt. front and Rt. rear.

That's interesting, a few years ago I worked with a fellow who told me that when he started working he wanted to be a mechanic. In his first year at trade school he was taught when checking brakes condition to check the L front and R rear first as that was the ones that wore the most. This was in drum brakes only days. He never continued to be a mechanic, became an electrician instead.

[Tom Wesenberg]

Originally Posted by 100IH

At this point I would remove the drums and look at the linings for the shiny spots that are the contact spots creating the heat. The high spots could be sanded or filed just a bit to speed up the wearing in process unless it is so out of position so as to indicate a further correction, such as modifying the roller tacks. A judgement call.

Right!
If it gets too hot it can wipe out the bearings. A few years ago I installed new brake pads on the front of my modern car during the dead of winter. They dragged a bit, but I figured the cold weather would keep them cool enough until they wore in. Well, it didn't, and I had to replace both front wheel bearing assemblies a couple months later.